1. Field of the Invention
The present invention relates to a tape cartridge made by housing a hub rotatably, around which a magnetic tape that serves as a tape-shaped recording medium is wound, in a cartridge case, and more particularly to a tape cartridge capable of achieving stable high speed running performance of a magnetic tape and higher storage capacity of a cartridge.
2. Description of the Related Art
A magnetic tape has been conventionally used for a magnetic recording and reproducing apparatus such as an audio tape recorder, a video tape recorder or an external storage apparatus of information processing equipment as an information signal recording medium for recording an information signal, a music sound signal, an image signal and the like. The magnetic tape is used while being wound around a tape reel.
FIG. 11 shows an example of the configuration of a tape cartridge 101 of related art.
The tape cartridge 101 of related art is configured to house a tape reel 106, around which a magnetic tape 105 is wound, rotatably in a cartridge case 104 formed by connecting an upper shell 102 and a lower shell 103 to each other. The tape reel 106 includes a hub 107 that is a core portion of the magnetic tape 105, and an upper flange portion 108 and a lower flange portion 109, both extending toward outside of their diameter from the upper end and the lower end of the hub 107.
A bearing member 110, a bearing cap 111 and a reel spring 112 are placed between the tape reel 106 and the upper shell 102. The lower surface of the tape reel 106 is exposed to the outside through a circular opening portion 113 formed at the central part of the lower shell 103. A chucking gear (not shown) engaging with a gear portion 114a at the upper end of a reel driving shaft 114 on the side of a recording and reproducing apparatus in an lower surface region (the outer surface region of the bottom portion of the hub 107) of the tape reel 106 exposed through the opening portion 113 is formed in ring-shape concentrically with the hub 107.
Next, when the tape cartridge 101 of related art is mounted in the recording and reproducing apparatus, the reel driving shaft 114 rises to engage the gear portion 114a thereof with chucking gear of the tape reel 106, and the tape reel 106 is pushed up to almost the central part of the thickness direction of the cartridge case 104 against the urging force of the reel spring 112. Consequently, the tape reel 106 is made to be rotatable. Then, the rotation driving force of the reel rotating shaft 114 is transmitted to the tape reel 106 through the chucking gear to rotate the tape reel 106. Thus the unwinding/winding of the magnetic tape 105 is performed.
As the prior art document information pertaining to the invention of this application, the following documents can be cited.    [Patent Document 1] Japanese Patent Application Publication No. 55-80842    [Patent Document 2] Japanese Patent Application Publication No. 09-115265    [Patent Document 3] Japanese Patent Application Publication No. 10-241232